The present invention relates to a prism optical system using a rotationally asymmetric surface, and an image display apparatus and imaging apparatus incorporating the same.
So far, it has been known to use a prism having a plurality of optical surfaces as a typical decentered optical system. When such a prism is used as an optical system adapted to observe an image display device, light exiting out from the display device enters the prism. Then, the light is reflected inside the prism, and exits out from the prism, arriving at the viewer s eyeball so that images may be viewed as enlarged virtual images.
For such an image-viewing optical system, JP(A) 2008-76429 discloses a prism that forms a primary image by at least three reflecting surfaces for projection onto the eyeball. JP(A) s 2007-94175 and 2004-325985 disclose eyeglasses with a hologram device mounted on their lens segment. Another optical system for image display apparatus has been proposed in JP(A) 2006-3879 disclosing that light is projected onto the eyeball by a light guide and an eyepiece lens.